Yellow dye.



UNITED STATES PATENT OFFICE.

EMIL MEYER, or ELBERFELD, GERMANY, ASSIGNOR TO FARBENFABR'IKEN VORM. FRIEDR.

' BAYER & 00., or ELBERFELD, GERMANY, A CORPORATION. OF GERMANY.-

' YELLOW mm.

Specificatioiiof Letters Patent.

Ifatented June e, 1908.

g V\ N o-o1a' with phthalicanhydrid and treatin the quinophthalone thus obtained withsul onating a ents. A yellow dyestufiis' thus'obtaine which has a stronger colorin power and is obtained in a better yield t an the known uinolinellow, produced by sulfonating t e con ensation lproduct derived from quinaldin and pht alic anhydrid. Furthermore the lakes of the new dye are faster to light than those ,of quinolin-yell'ow.

In order to illustrate the new process more fully the following example is given, the parts being by weight:

Example- 177.5 parts of para-chloroquinaldin (obtainable by treating para-chloroamlin with acetaldehyde and hydrochloric acld) are heated with 148 parts of phthalic anhydrid to 210 C. After 5 to 6 hours the reaction is complete. The ohloroqhuinophthalone is washed with little alco 01 and dried. It is a yellow powder soluble in alcohol with a ellow color. The alco olic solutiondyes wool or silk 'yello'w shades.

1 part of the new chloroquinophthalone is mixed with 3 arts of fuming sulfuric acid (38 er cent. 0 S0 The mixture is then slow y heated to 8090" and kept at this temperature during 4-5 hours. Subsequently the product of the reaction is poured into times its quantity of water and from the li uid thus obtained the sulfonic acid is precipitated by the addition of common salt. The sodium salt of this sulfonic acid is a yellow. powder soluble in concentrated sulfuric acid with a yellow color and soluble in water-with a yellow color which turns reddish-yellow on addition of dilute alkali. 1-

The new dyestufi dyes wool and silkfrom acid baths greenish-yellow shades.

Having now described my invention and in what mannerthe same is to be performed, what I claim as new-and desire to secure by Letters Patent'is v The herein-described dyestufi obtainable by condensing 7 EMIL MEYER. [L.s.]

Witnssesz- Or'roKome, F p WM.'WASHINGTON BoNNsUnEx.

ara-chloroquinaldin with phthalic anhydri and treatin .the uinoph- 

